Group-III element nitride semiconductor substrate

Abstract

There is provided a large-diameter Group-III element nitride semiconductor substrate including a first surface and a second surface, in which, despite its large diameter, variations in quality in the first surface are suppressed. A Group-III element nitride semiconductor includes: a first surface; and a second surface, wherein the Group-III element nitride semiconductor substrate has a diameter of 100 mm or more, and wherein the Group-III element nitride semiconductor substrate has a coefficient of variation of a yellow luminescence intensity in a range corresponding to 88% or more of an entire region of the first surface of 0.3 or less based on a photoluminescence spectrum obtained through photoluminescence measurement of a range of the entire region of the first surface.

What is claimed is: 
     
         1 . A Group-III element nitride semiconductor substrate, comprising:
 a first surface; and   a second surface,   wherein the Group-III element nitride semiconductor substrate has a diameter of 100 mm or more, and   wherein the Group-III element nitride semiconductor substrate has a coefficient of variation of a yellow luminescence intensity in a range corresponding to 88% or more of an entire region of the first surface of 0.3 or less based on a photoluminescence spectrum obtained through photoluminescence measurement of a range of the entire region of the first surface.   
     
     
         2 . The Group-III element nitride semiconductor substrate according to  claim 1 , wherein the coefficient of variation is 0.2 or less. 
     
     
         3 . The Group-III element nitride semiconductor substrate according to  claim 1 , wherein the Group-III element nitride semiconductor substrate has a coefficient of variation of a yellow luminescence intensity in a range corresponding to 92% or more of the entire region of the first surface of 0.3 or less based on a photoluminescence spectrum obtained through photoluminescence measurement of a range of the entire region of the first surface. 
     
     
         4 . The Group-III element nitride semiconductor substrate according to  claim 3 , wherein the coefficient of variation is 0.2 or less. 
     
     
         5 . The Group-III element nitride semiconductor substrate according to  claim 1 , wherein a measurement interval Y in the photoluminescence measurement is 1 mm or less. 
     
     
         6 . The Group-III element nitride semiconductor substrate according to  claim 1 , wherein the Group-III element nitride semiconductor substrate has a warping of 100 μm or less. 
     
     
         7 . A Group-III element nitride semiconductor substrate, comprising:
 a first surface; and   a second surface,   wherein the Group-III element nitride semiconductor substrate has a diameter of 100 mm or more,   wherein the Group-III element nitride semiconductor substrate has a coefficient of variation of a yellow luminescence intensity in a range corresponding to 88% or more of an entire region of the first surface of 0.3 or less based on a photoluminescence spectrum obtained through photoluminescence measurement of a range of the entire region of the first surface,   wherein a measurement interval Y in the photoluminescence measurement is 1 mm or less, and   wherein the Group-III element nitride semiconductor substrate has a warping of 100 μm or less.   
     
     
         8 . The Group-III element nitride semiconductor substrate according to  claim 7 , wherein the Group-III element nitride semiconductor substrate has a coefficient of variation of a yellow luminescence intensity in a range corresponding to 92% or more of the entire region of the first surface of 0.3 or less based on a photoluminescence spectrum obtained through photoluminescence measurement of a range of the entire region of the first surface. 
     
     
         9 . The Group-III element nitride semiconductor substrate according to  claim 7 , wherein the coefficient of variation is 0.2 or less. 
     
     
         10 . The Group-III element nitride semiconductor substrate according to  claim 8 , wherein the coefficient of variation is 0.2 or less.